Synthesis, characterization and catalytic behaviour of ansa-zirconocene complexes containing tetraphenylcyclopentadienyl rings: X-ray crystal structures of [Zr{Me2Si(η5-C5Ph4)(η5-C5H3R)}Cl2] (R=H, But)

A novel alkenyl-substituted ansa-zirconocene complex with dual application as olefin polymerization catalyst and anticancer drug

“…The Cent(1)-Zr(1)-Cent(2) angle of 127.1°for 5, is similar to those reported for other ansa-zirconocene complexes [3,[24][25][26][27][28]. The Cl(1)-Zr(1)-Cl(2) angle for 5 (97.85(4)°) is similar to those recorded for related tetramethyl substituted ansa-zirconocene complexes [3,[24][25][26][27][28].…”

“…The Cl(1)-Zr(1)-Cl(2) angle for 5 (97.85(4)°) is similar to those recorded for related tetramethyl substituted ansa-zirconocene complexes [3,[24][25][26][27][28]. The distances, Zr-Cl ca.…”

Preparation of titanocene and zirconocene dichlorides bearing bulky 1,4-dimethyl-2,3-diphenylcyclopentadienyl ligand and their behavior in polymerization of ethylene

“…The crowding of the active site then influenced either formation of cationic centre by cocatalyst or insertion of ethylene into Zr-C bond. The influence of steric crowding on activation of bulky [Zr{Me 2 Si(g 5 -C 5 Ph 4 )(g 5 -C 5 H 3 t-Bu)}] by MAO was recently elucidated by DFT calculation, which showed that the abstraction of a methyl group to form the cationic active species was endotermic (8.5 kcal/mol) [23]. Moreover, the DFT calculation showed that barrier for insertion of ethylene into Zr-Me bond is relatively high (12-24 kcal/mol for [Cp 2 ZrMe] + ) [24,25].…”

3D-QSAR as a Tool for Understanding and Improving Single-Site Polymerization Catalysts. A Review

“…This has been confirmed both experimentally and theoretically. 21 In the sections below, catalyst/cocatalyst interactions are examined in terms of their effects on the interpretation of QSAR results. Prior to this, we describe the basic principles of the use of 3D-QSAR tools and the information they provide.…”

“…Several studies have also theoretically addressed catalyst behavior during polymerization. − Our group has actively contributed to this field with a number of computational studies. − For this type of study, density functional theory (DFT) has allowed the treatment of polymerization catalyst systems using the computational resources available at the time over the past 20 years.…”